If it has the same cellular structure as something then it is that something, regardless of personal belief. Thats the beauty of science, its often rather easy to identify if something is the same on a factual, definitive basis, as much of science can be measured in absolutes.
Cancer is the body's own cells, refusing to die. Those cells are extremely specific. A primary cancer, let's say breast, invades breast tissue, because they are composed of breast tissue suffering from a mutation which means cells no longer die in order to be replaced by new, young, healthy cells (autophagy). If those cancerous breast cells travel around the body (usually via the lymphatic system, but potentially also via the blood) they can invade the healthy tissues of any other body part and start growing there. Most commonly the bones, or the liver, but it can be brain, peritoneum, even eyes. Anywhere. But no matter where they metastasise, they remain breast cells. They are identifiable as such upon biopsy. They are not ever cells of that body part. They remain of the breast.
If someone has no cervix, then they do not have cervical cancer. The cells will be identifiably of the originating body part. There was an extraordinary case of a transplant donor, who had undiagnosed metastatic breast cancer. Four organ recipients ended up with her breast cancer growing in their bodies. It was possible to trace the cancer back to a deceased organ donor's breast tissue, across every recipient.
Cancer is specific at a cellular level. Parabasal cells - the 'similar' in the study you cite - are found in cervical smears where the patient has an endochrine disorder - too low oestrogen and/or too high androgen (male hormones). The study further notes that the cells are, "similar" which you have misinterpreted as, 'the same cellular structure as a cervical cell.' They are not cervical because the body's DNA has coded instructions for growing every single body part. Cosmetic surgery can't alter someone's DNA. Men can't grow cervical cells; the DNA lacks the capacity.
Endochrinology is often very important in cancer, affecting treatment pathways, and disease processes. That's relevant and important in trans people's cancers if they have been treated with hormones, as it is in women on HRT for example, and it's wholly right that appropriate, informed care should be provided. That doesn't mean someone without cervical cells, and without DNA capable of creating such cells, suddenly has them. Pretending that it is cervical cancer is not in the interests of the patient, because that patient needs specialist care.
If a trans man is likelier to engage with smears if the leaflet talks about, "people with a cervix", then there needs to be literature and an approach from the clinicians that adopts that language, for that cohort. We need to help people. That's the bottom line. But you know what isn't inclusive? Erasing women from all the literature, in case accurately reflecting biology, anywhere, might upset a small minority. That minority deserve respectful literature for their needs, just as women of immigrant communities, who don't speak English fluently, need and deserve leaflets that they can read and understand in their own language. But the main literature should state women, and female. Because that's the form that benefits the vast, vast majority of patients, and their needs, interests, and feelings matter too.
Rendering language around women problematic unless it centres a small minority of males, or those who identify as men, is misogynist. The word 'woman' has had a meaning - adult human female - for centuries - centuries in which women were property, and subject to men's whims and demands, and now, finally, we have rights, a concerted attempt is being made to remove any means of accurately identifying who we are. And, please note, that it's not a demand made around men. Nobody's insisting prostate cancer information erases men, just as the Scots government left the legal definition of 'man' well alone. As always, it's women who are at the sharp end, and whose rights - rights based upon recognition of us as a legal class of people - are threatened.
There's a reason 'misogyny' has the 'gyny' in it. Hatred of women is biologically-founded: demanding that women ignore that is about as progressive as demanding that black people abandon all reference to race. You can't counter a bigotry you are not allowed to name. Biology matters. It's the foundation of women's oppression. Biology is the reason. Gender is how.
Eve was a woman. That's why they named the charity.
And this cancer survivor doesn't need some self-important, officious little dipshit on Instagram (with a drama degree. You shock me) to tell me I'm a woman, even without various bits of my female anatomy. My every cell encodes that I am one. In hundreds of years, if they dig up my skeleton, they'll know that I was one. I'm so tired of the fatuous, facile wankery trotted out mindlessly over all of this. Be who you want, live as you like, and I'll fight for your right to do so, and your right to be free of harassment, abuse, and discrimination. But biological facts remain. They will outlive us all, and they don't care what you think.